Separable pulley



(N Model.) -2 sheets-sheet 1.

H. J. GILBERT. SB'PARABLB PULLEY.

No.I 451,038.

Patented Apr. 28,l 11891.

(No Model.) 2 Sheets-Sheet 2.

H. J. GILBERT. SEPARABLE PULLBY.

Wwavew UNTTnn STATES PATENT @erica HENRY J. GILBERT, OF. SAGINAW,MICHIGAN.

SEPARAB LE PU LLEY.

SPECIFICATION forming part of Letters Patent No. 451,038, dated April28, 1891.

Application tiled February 13, 1891. Serial No. 381,272. (No model.)

To all whom, t may concern:

Be it known that I, HENRY J. GILBERT, a citizen of the United States,residing at Saginaw, in the county of Saginaw and State of Michigan,have invented certain new and useful Improvements in Separable Pulleysand the Method of Constructing the Same, of which the following is adescription, reference being had to the accompanying drawings, formingpart of this specification.

My invention relates to the pulley itself, whose particular novelconstruction enables it tobebuilt more cheaply and be made of greaterstrength than has been usual heretofore, and also to a novel method ofbuilding up sepable pulleys generally, whereby the manufacturer isenabled to carry in stock a supply of partly-constructed pulleys orpulley-sections from which he can quickly build up complete pulleys ofvarying widths of face, as ordered.

The novelty of my invention will be further set forth herein, andspecifically pointed out in the claims.

In the accompanying drawings, Figure l represents a side elevation of asection of my improved pulley. Fig. 2 is a cross-section of two suchsections before the hub-blocks are bored and the clamping-bolts appliedon the line 2 2 of Fig. l, with a section of rim and hub-blockinterposed between them; Fig. 3, a cross-section of a complete pulleybuilt up of the parts shown in Fig. 2, with the covering-rings added tothe sides of the rim. Fig. 4 is a side elevation of one set of spokes ofmy improved pulley with the hub portions of the spokes in section toshow the dovetail keys by which they are locked together. Fig. 4 is across-section corresponding to one of those in Fig. 2, but without therim-section. Fig. 5 is an enlarged perspective of the hub portion of oneof the spokes, showing the dovetail key-seats therein. Fig. 6 is aperspective of the dovetail-key, and Fig. 7 is a perspective of one ofthe hub-blocks.

The same letters of reference are used to indicate identical part-s inall the figures.

Each section of the pulley, Fig. l, is composed either of one or twosets of spokes or arms A, preferably two, and a rim-section B, intowhich they are fitted and secured. The butt-ends of the spokes of eachset are suitably shaped to it snugly against each other and form ahub-section, as shown. Their abutting faces have dovetailed key-seats Cout in them, as shown in Figs. land 5. These seats are adapted toreceive dovetail locking.keys D, an enlarged view of one of which isshown in Fig. G. One of these keys is driven into the seats between eachpair of spokes and firmly locks them together. The keys are preferablyimmersed in glue, and glue applied to the abutting faces of the spokesbefore the keys arevdriven in to increase the strength of the joint.Then a set of spokes have been thus locked together, if thepulley-section is to containl only one set of spokes they are set into arim-section B, built up of arc-shaped cants and -provided withtransverse bores and slots, Fig. l, for the reception of the outer endsof lthe spokes. The tenons on the latter are so shaped as to be securelylocked in the bores of the rim by the insertion of the oval locking-keysE. This method of locking the ends of the spokes to the rim, however, isnot new, and any other suitable method may be employed.

From the pulley-sections, each composed of a single set of spokes and arim-section, as above described, the complete pulley may be built up inthe manner hereinafter set forth.; but, as I prefer to form each sectionof two sets of spokes instead of one, I will first describe the methodof building such a section.

The spokes of each set are first locked together at their butts, asshown in Fig. Ll, but their outer ends are not tenoned. One set ofspokes is then placed upon the other, with a rectangular block F (shownin dotted lines in Fig. l and in perspective in Fig. 7) between them,while between the adjacent faces of the outer ends of the spokes of eachpair is placed a spacing or strengthening block G, Figs. 2, 3, and 4t.The joints between the butts of the spokes and hub-blocks and betweenthe outer ends of the spokes and the blocks G are glued, and in additionthe spokes may be nailed or doWeled to the blocks. When the two sets ofspokes have been fastened together in this manner, the outer ends of thespokes, with the interposed blocks G, are tenoned to the shape shown inFig. 4C. The spokes are then ready to berapplied to a rim-section in thesame manner as the single set of spokes before described, therim-section being` simply composed of more layers of eants to make itswidth correspond tothe two sets of spokes instead ot' a single set.

From the pulley-sections above described, whether composed of one or twosets ot spokes, the complete pulley is built up as tollows: Between thehubs of cach two sections is placed another hub-block F', and betweenthe two rim-sections a third rim-section B, there being no spokes inthis middle section and the hub-block F being in no way connected withthe rim-section B. rlhe three sections are securely nailed or doweledand glued together to form the body of the complete pulley, after whichit is sawed in two on the line 2 2 of Fig. l to separate it into halves.Holes are bored through the hubblocks F F transversely to the line 2 2for the reception of the bolts H, by which the l two parts of the pulleyare to be clamped together. The hub of the pulley is then bored out tothe desired diameter, the inner ends ot the spokes having been lettroughand irregular up to this time. The covering or finishing rings I I arethen applied to the opposite sides of the rim and the pulley iscomplete, as shown in Fig. 3. The ends of the divided covering-rings I Iare made to overlap the lines of division of the rim of the pulley tohide the joints and prevent lateral displacement, as usual. The pulleyis then turned in the usual manner.

From the above description it will be seen that in the completed pulleythere is between the rims B B of each two adjacent sections of which thepulley is composed a rim-section B', which has no spokes in it, and istherefore not weakened by having holes and slots in it, as have theportions of the rim which receive the spokes. It will also be understoodthat the bolts H for clamping the pulley together pass through thehub-blocks alone and not through the spokes, so that thelatter are notweakened at their inner ends.

So far as the particular construction of my improved pulley isconcerned, by locking together the butts of the spokes ot' each set withthe dovetail keys and by securing the separate sets of spokes togetherwith the interposed hub-blocks F and spacing-blocks G, I am enabled touse much lighter material for the spokes without lessening the strengthof the pulley. I am also enabled to cut the spokes from thin lumber(thinner than indicated by the proportions of the drawings) and to setthem edgewise in the pulley, which lessens the tanning action of thepulley, and thereby decreases the resistance offered by the air to itsrevolution.

By utilizing thin lumber for the spokes I am enabled to materiallycheapen the construction of pulleys of this class. In actual practice Iuse scrap lumber for portions of the hub ends of the spokes. In suchcase the body of the spoke is made of nearly the same width from theinner end to the rim, tapering slightly, and the beveled side portionsof the butts of the spokes are composed oi separate pieces glued to thebody ot the spoke, as indicated by the dotted lines a a in Fig. 5.

The special advantage of building up the complete pulley frompreviously-construeted sections in the manner described is that itenables a manufacturer to keep on hand a stock which will meet therequirements of the trade with a much less investment of capital.Inasmuch as pulleys for different uses must vary greatly not only indiameter, but also in width of face, a manufacturer, in order to readilymeet the demand for them, has heretofore been obliged to carry in stocknot only a complete line of pulleys of all the different diametersusually called for, but also a complete `line of such pulleys in all thedifferent widths generally needed. My invention enables him to avoid thenecessity of carrying a stock of pulleys ot different widths, for byhaving on hand a complete stock of the pulley-sections of the same widthbut of different diameters he can upon receipt of an order quickly buildup a supply of pulleys of any desired width. This enables him to carry astock which will meet the requirements of the trade with about one-halfthe capital which has heretofore been necessary.

So far as concerns my novel method of building up complete pulleys ofdifferent widths from previ'ously-constructed pulleysections, myinvention is not limited to the particular con struction of suchsections, either as the manner of securing togetherthe spokes of eachset or otherwise, but contemplates a method as broad as the terms of myrespective claims imply.

IIaving thus fully described my invention, I claiml. Theherein-described pulley-section, composed of two sets of spokes A, thespokes of each set having their recessed butts locked together bydovetail keys D, the hub-block F, interposed between the hub portions ofthe two sets of spokes, and the rim-section B, in which the outer endsof the spokes are secured.

2. The herein-d eseribed pulley-section, composed of two sets of spokesA, the spokes of each set having their recessed butts locked together bydovetail keys D, the hub-block F, interposed between the hub portions ofthe two sets of spokes, and the blocks G, interposed between the outerends of the spokes of each pair, and the rim-section B, in which theouter ends ot-the spokes are secured.

3. The herein described method of constructing pulleys of differentwidths, consisting in first forming pulley-sections, each composed ot aset of arms or spokes and a rimsection, and then securing two or more ofsaid sections together with an interposed hubblock and rim-section toform the complete pulley of the desired width.

4. The herein described method ot' constructing pulleys of differentwidths, consisting in tirst forming pulley-sections, each eom IOO IIO

posed of a rim-section and zt set of spokes dovetailod together' ettheir butt-ends, and then securing said sections together withinterposed hub-blocks and rim-sections to form the complete pulley ofthe desired Width.

5. The herein-described method of constructing pulleys of differentwidths, consisting in first forming pulley-sections, each Colnposed of arim-section and two sets of spokes, the two sets of spokes being securedtogether at their butt-ends with an interposed hubblock, and thensecuring said sections t0- gether With other interposed hub-blocks andrim-sections to form the complete pulley of the desired Width.

6. The herein-,described method of oon-

